webpack.config.js

const path = require("path")
const webpack = require("webpack")
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');

module.exports = {
  entry: "./src/index.js",
  mode: "development",
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        exclude: /(node_modules)/,
        loader: "babel-loader",
        options: { presets: ["@babel/env"] }
      },
      {
        test: /\.css$/,
        use: ["style-loader", "css-loader"]
      }
    ]
  },
  resolve: { extensions: ["*", ".js", ".jsx"] },
  output: {
    path: path.resolve(__dirname, "dist/"),
    publicPath: "/dist/",
    filename: "bundle.js"
  },
  devServer: {
    contentBase: path.join(__dirname, "/"),
    port: 3000,
    publicPath: "http://localhost:3000/dist/",
    watchContentBase: true,
    historyApiFallback: true,
  },
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
          mangle: {
            keep_fnames: true,
          },
        },
      })
    ],
  },
  plugins: [new webpack.HotModuleReplacementPlugin()]
}